package com.atguigu.gulimall.product.service.impl;

import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;
import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.stereotype.Service;

import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1.查出所有分类
        List<CategoryEntity> categoryEntityList = baseMapper.selectList(null);
        //2.组装成父子的树形结构

        List<CategoryEntity> level_1_Menus = categoryEntityList.stream()
                //2.1找到所有的一级分类
                .filter(categoryEntity -> categoryEntity.getParentCid() == 0)
                //2.2设置子类对象
                .peek(menu-> menu.setChildren(getChildrenList(menu,categoryEntityList)))
                //2.3自然排序
                .sorted(Comparator.comparingInt(menu->menu.getSort()==null?0:menu.getSort()))
                .collect(Collectors.toList());
        //3.返回查询结果
        return level_1_Menus;
    }

    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO 1、检查当前删除的菜单，是否被别的地方引用

        // 2、逻辑删除 在实体类中，在逻辑删除标识字段，添加逻辑删除注解，即可。
        baseMapper.deleteBatchIds(asList);
    }

    /**
     * 递归查询并设置子类对象
     * @param root
     * @param all
     * @return
     */
    private List<CategoryEntity> getChildrenList(CategoryEntity root,List<CategoryEntity> all){
        List<CategoryEntity> childrenList = all.stream()
                .filter(categoryEntity -> categoryEntity.getParentCid().equals(root.getCatId()))
                .peek(categoryEntity -> categoryEntity.setChildren(getChildrenList(categoryEntity, all)))
                .sorted(Comparator.comparingInt(menu->menu.getSort()==null?0:menu.getSort()))
                .collect(Collectors.toList());
        return childrenList;
    }

}